Description of the Related Art
The invention relates to a television signal receiver comprising an intermediate frequency (IF) filter having an intermediate frequency filter group delay, and an intermediate frequency demodulator coupled to said intermediate frequency filter. The invention also relates to a method of receiving television signals. The invention can be used in both wide aspect ratio and standard aspect ratio television receivers.
Within the transmission of B,G/PAL, a precorrection of group delay is performed at the transmitter. The necessity of this group delay precorrection dates from the time when it was difficult and expensive to make receiver IF-filters with a flat group delay response characteristic. Nowadays, receiver IF-filters with a flat group delay response are available on the market at relatively low prices. Consequently, there is no longer any need for group delay precorrection.
There is a strong drive, coming from German broadcasters, to cancel the group delay precorrection process. They want to do this in two steps, viz. by halving the amount of group delay precorrection by 1994, and by cancelling the group delay precorrection entirely by 2001. However, cancelling the transmitter group delay precorrection causes a noticeable loss of sharpness and a chrominance/luminance delay difference in television receivers which still expect the television signal to have undergone the transmitter-sided precorrection.